ginput

Graphical input from mouse or cursor

Syntax

[x,y] = ginput(n)[x,y] = ginput[x,y,button] = ginput(...)

Description

ginput raises crosshairs in
the current axes to for you to identify points in the figure, positioning
the cursor with the mouse. The figure must have focus before ginput can
receive input. If it has no axes, one is created upon the first click
or keypress.

[x,y] = ginput(n) enables
you to identify n points from the current axes
and returns their x- and y-coordinates
in the x and y column vectors.
Press the Return key to terminate the input before
entering n points. Specify n as
a positive integer.

[x,y] = ginput gathers an
unlimited number of points until you press the Return key.

[x,y,button] = ginput(...) returns
the x-coordinates, the y-coordinates,
and the button or key designation. button is a
vector of integers indicating which mouse buttons you pressed (1 for
left, 2 for middle, 3 for right), or ASCII numbers indicating which
keys on the keyboard you pressed.

Clicking an axes makes that axes the current axes. Even if you
set the current axes before calling ginput, whichever
axes you click becomes the current axes and ginput returns
points relative to that axes. If you select points from multiple axes,
the results returned are relative to the coordinate system of the
axes they come from.

Note:
MATLAB® returns errors such as the following if you start MATLAB with
the –noFigureWindows or –nodisplay flag
and then run ginput:

Error using ginput (line 31)
Terminal mode is no longer supported

Definitions

Coordinates returned by ginput are scaled
to the XLim and YLim bounds
of the axes you click (data units). Setting the axes or figure Units property
has no effect on the output from ginput. You
can click anywhere within the figure canvas to obtain coordinates.
If you click outside the axes limits, ginput extrapolates
coordinate values so they are still relative to the axes origin.

The figure CurrentPoint property, by contrast,
is always returned in figure Units, irrespective of axes Units or
limits.

Examples

Pick 4 two-dimensional points from the figure window.

[x,y] = ginput(4)

Position the cursor with the mouse. Enter data points by pressing
a mouse button or a key on the keyboard. To terminate input before
entering 4 points, press the Return key.

In this example, plot rescaled
the axes x-limits and y-limits
from [0 1] and [0 1] to [0.20
0.65] and [0.40 0.75]. The rescaling
occurred because the axes XLimMode and YLimMode are
set to 'auto' (the default). Consider setting XLimMode and YLimMode to 'manual' if
you want to maintain consistency when you gather results from ginput and
plot them together.